I've been toying with the idea myself, but my bike is very much a tool for job and the patina of scratches are just part of it. There is one scratch that bugs me though, as it was due to my laziness in strapping a ladder inside the back of my van properly, and it fell and hit the bike. I wasn't happy with my self.
I have a hankering to nut and bolt the whole bike, and to spray it all orange. The downside of doing so, is that it'll soon get scratched again, so isn't really worth the effort and expense.
Putting wear and tear and scratches into some form of context. This is my rear chain and seat stays after one year of use.
If the bike is sentimental to you, and you value it's appearance, then it could be worth it. Minor scratches could also be worth re touching, but a full nut and bolt rebuild with respray, is never going to be financially viable.
I used to complete very high end restorations of classic GP racing motorcyle's, and I always felt that the best part of the bike, was also the part that was never restored (if that makes sense) Loosing the original patina, takes away too much authenticity.